alt Hacker NewsCompaq dropped the bombshell about canceling Alpha just before Win2k RTM, surprising both Microsoft team involved and Compaq-side team.
Microsoft continued to use 2000 on Alpha to work out bugs in 64bit support since it was the only 64bit platform they had supported that had operational hardware (support for PPC was only for 32bit), making it important bit in support of Itanium and soon later amd64 ports.
Some of the details made for Alpha support (including extended support for software like FX!32) are now backbone of x86-on-ARM support in windows ARM builds
As a side-note, it's interesting that all of the released versions of NT on Alpha were 32 bit.
Raymond Chen has a blog post[0] about using Alpha to develop 64bit Windows before Itanium hardware was available.
Virtually Fun has some more excellent background on finding a compiler for 64bit Windows[1], finding a copy of Windows 2000 64bit for Alpha AXP[2], and a detailed article about making an ISO from the found copy.
[0] https://learn.microsoft.com/en-us/previous-versions/technet-...
[1] https://virtuallyfun.com/2023/05/05/hiding-in-plain-sight-th...
[2] https://virtuallyfun.com/2023/05/15/windows-2000-64-bit-for-...
[3] https://virtuallyfun.com/2023/06/26/axp64-2210-installation-...