It is quite amusing to observe the dynamic in this group. All those who ganged up on Alan for his complaint about the second dose did so thinking they are defending Bided administration's decision. Now when it turns out it was actually Trump administration's decision, the gang will have to realize they were defending the enemy and that they should have to then side with Alan (gasp!) in criticism of the decision

I don't think you are following along closely enough.
Alan is against expanding the patient pool to include people, including young people, who have certain comorbidities, and releasing the second doses, both of which were Trump decisions. He has articulated that he is against expanding the patient pool because he thinks old people like him should get the vaccine first, and he is against releasing the second doses because, having gotten his first dose, he wants to make sure he gets his second dose. Alan's positions are basically me now, me later, which is okay if you can justify them.
I have asked Alan why he thinks old people should get the vaccine first, and he has responded because old people are more likely to die if they get COVID. My response is: "So what?" I'd at least like to hear an argument from him about why his life is more valuable than the life of a little girl, with or without a comorbidity. So far, crickets.
I haven't been involved in the argument about releasing second doses, except to the extent of noting that when Secretary Azar announced on January 12, 2021 they were releasing the second doses, there weren't any because someone somewhere in the Trump administration had already released the second doses at the end of December, so it was clear that Azar, the head of HHS, didn't have any idea what was going on with respect to the distribution of vaccines, which I deemed a shortcoming. It was also an admission that we were out of vaccine, which I deemed a shortcoming as well. Others have argued that it is better to have twice as many people with 80% immunity than half as many people with 95% immunity. I haven't weighed in on that discussion. Neither has Alan. As far as I can tell, he just wants his second dose because he wants his second dose.
My arguments are independent of whether they are Trump policies or Biden policies. The primary problem with Alan's positions is that they are frequently based on false facts and supported by arguments riddled with logical fallacies. They also happen to parrot Trump's positions, but that's not the primary reason I disagree with Alan. It's the false facts and logical fallacies. Oh, and maybe because Alan's positions start out as bald assertions, and we don't get the false facts and logical fallacies until we point out that his bald assertions are nonsense. Then we get the false facts and logical inconsistencies, and when we point out that they are false facts and logical fallacies, Alan tries to change the subject, usually with the logical fallacy of whataboutism.
I think Biden's positions were to release the second doses and not expand the patient pool, but I couldn't swear to it. Maybe it is the other way around. It being a Trump position or a Biden position is irrelevant in my discussions with Alan on these topics. Of course I did note that it was out of character for Alan to be anti-Trump, but I don't think he knew which positions were Biden's and which were Trump's to begin with, probably because Trump's positions changed and Alan didn't keep up.