Garmin express and webupdater say I have latest software = 2.90

Yes, APAC firmware version comes later.

Policy or difference ?

Is that Garmin policy or is there some difference in the APAC version?
Would be nice if the release process and notes mentioned or discussed this. If it's a separate stream of software shouldn't there be a different release number?
We now have a 3.41 beta , can that be loaded on an APAC F5X?

I can see a fairly significant but random undercounting of steps in some activities on 2.9. I note there are some fixes in 3.3 in this area so curious to know if they solve it.

I am in Melbourne and I updated to 3.30 the day after it was released.

There is nothing preventing you from loading the 3.41 beta onto your watch. Follow the instructions, it should work without any issues.

I left this a few days as I thought it might take time to propagate but i'm still not getting the 3.3 update.
I've tried synch, garmin express and webupdater. They all say i have the latest software 2.9.
Are there differences for the APAC regional variants that have not yet been released ?

I am with you too eagerly awaiting 3.3 to be released soon. My 5x is an APAC version as well.