Dear Alias @Rickster
Why are You coming so late with this question??
There were other threads on the issue which were very quickly closed by the gCaptain government and I still do not understand why .
If You read them, you surely would find the following :
and in above thread there were some other inputs reflecting my opinion and speculations. Likewise there were many other very interesting comments provided by other knowledgable participants.
My questions " what would you do ?" was completely ignored and it was declared as :
I am not sure why it is impossible to answer or to elaborate on " what would you do?" question. It is more easy and I think fair instead of iffing or saying what "they " should do having the hindsight.
Nobody bothered to give it a try since March 19-22 nd and why? I do not know.
And yet there were some in this thread like @Ladder who hinted something very obvious and rather logical and even obligatory :
and He mentioned it before " what would you do ?" project of mine.
I have clipped Solong data sheet below with some very important detail which i will use to reply to somebody, who needed ALL 38 DAYS since March 19th to finally admit something what He/She obstinately ignored in what seems “patriotic” zeal and passion.
My congratulations . If this is taking such a long time to think , then it’s better for some to call the master SOONER then LATER by application of slow thinker factor. Upon reflection it seems that my standard night order " call me before shit happens" gets a new important meaning in relation to this particular case.
Who else in this noble congregation of old salts and young pistols knew what to do???
Reading relevant posts here is an absolutely exciting experience as it is a proverbial gold mine of ideas and opinions. I simply love it as You never know where the EUREKA moment will hit You .
Well, the person who did not participate at all in this discussion on Stena misfortune was nobody else but his Excellency Owner of gCaptain and supporter /activist of US Merchant Marine his majesty Capt. John Konrad .
And i have opened on purpose and with deliberation a thread with his grand speech and vocal performance which is here:
Regret to say it got a whooping 113 views and ZERO comments as nobody dared to challenge His Majesty on his story.
But I found it unbelievable, that among the crowds of experts here only Capt John Konrad knows what is ITU booklet and what it contains and how it can be used especially that nowadays, it is available in electronic format at least in pdf. And this booklet i had on all my ships, it is available in Owners/Managers offices and especially it is available in all shore side institutions like coastguards , pilot officess , VTSes , Harbour Masters, and others dealing with ships traffic and traffic safety in their area of responsibility what has been confirmed by the initial MAIB report.
I think all who care to read my input can already sense the direction of my drift.
Now to your spiel. There is no “it fits all” recipe in this case and writting a procedure for this case which supposedly could have prevented the collision is a fallacy without knowing all the facts.
We do not know what Stena crew did prior the event .The only thing that was revealed was that 2nd off took watch at midnight what does not clearly indicate if He/She was on the bridge at kaboom moment and what He/She was doing there prior kaboom.
May be He called Solong ??? I do not know .
But seeing the media reaction and reporting and glorification of Stena actions after collision one would expect that " mayday relay" call recording would be accompanied by frantic Stena VHF calls on Ch 16 and other, trying to allert the incoming vessel of an impending danger. It would surely boost the public opinion view of the professioinalism of Stena crew regarding watch keeping and application of so called due diligence while doing it.
Same with the getting M/E ready. We do not know what was the state of readiness of the plant. Could be the standard 60 minutes , could be half an hour , could be 15-20 minutes depending on the circumstances. In some cases it can be immediately available . Such conditions have been described in another thread .
W/O M/E one can release more shackles but we do not know how many were out at kaboom moment and prior. So one can speculate ad noseam . Trust the investigation will reveal all facts and answer all questions.
On the hook your options are very limited and even if done may be ineffective or even exacerbate the situation as there is a risk the bandit will wake up on the bridge and yell " Blatz or yob tvoyu Matz" and turn in the heat of the moment in the wrong direction.
Sounding signals as per regs is a good option re due diligence and my favourite option would be to call them . Why I will explain later . THE QUESTION IS WHEN ?? and this is another debatable item.
Surely by calling the bandit You will not wake up and upset the US Master who as per one crown witness here is getting 30 grand per month by sleeping 12 hrs per day.
So my Dear . Read ALL the posts/threads and attachments/links with good info in it and give them the spiel like they have never heard in their life 
In addition I have inserted here the clip with my interrogation of AI. All very valuable and recommended.
The problem I have with AI in this clip is the " give way vessel" but all knowing AI seems to know better or got a shitty teacher.
Trust i did my best in exhausting not only You but all others scrolling on their screens my blah blah.
Sorry.
Cheers.
PS. And by the way. While visitng all US coasts and ports have noticed the most favourite sport of US navigators is calling each other to determine and clarify the safe passage condition.
Wonder why this interesting habit was forgotten in Stena case( if of course they did not call out)