It may be different for you, but here in the UK I've been able to sync frequently and reliably on Orange over the last week or two, after I gave up waiting for an elusive Green! Sometimes, even though the FTM toolbar icon shows a Red alert, if I try to sync I get Orange and can then proceed. Other times, even though the toolbar icon has only an orange alert, when I try, I get a Red and can't sync, but retrying a little while later usually gets me an Orange eventually, and I can re-sync my tree (about 3,300 people). I've usually got a handful of changes, and have been syncing them in either and/or both directions (I tend to do my research on Ancestry, but general housekeeping like editing profile photos and rationalising addresses on FTM).
Of course, you do this at your own risk, and should always take a backup before any sync attempt. It would be safest to wait until you have a Green status as strongly recommended by Ancestry/FTM. Hopefully we'll be back to "Greens" later this week when (or if?) Ancestry's maintenance upgrades are completed.
As others have said, its very disappointing that Ancestry haven't at least put up a warning banner on the website, as they certainly used to do in the past for service issues. That might at least reduce the number of endless "why is it so slow?" queries. I even got an email from them this morning, expecting it to be some sort of more detailed explanation for the disruption and an apology, but instead it was simply some "trumpet blowing" about the addition of the 1939 register. That's great, incidentally, but it seems significantly poorer than FMP's 1939 implementation, which has more accurate transcriptions and things like proper street addresses which, unlike in Ancestry, are shown in the transcription even if they're obscured by an "officially closed" in the image itself. It makes it more difficult to decide if I should continue with my FMP subscription, which I use mainly for the 1939, as well as Ancestry.
Of course, you do this at your own risk, and should always take a backup before any sync attempt. It would be safest to wait until you have a Green status as strongly recommended by Ancestry/FTM. Hopefully we'll be back to "Greens" later this week when (or if?) Ancestry's maintenance upgrades are completed.
As others have said, its very disappointing that Ancestry haven't at least put up a warning banner on the website, as they certainly used to do in the past for service issues. That might at least reduce the number of endless "why is it so slow?" queries. I even got an email from them this morning, expecting it to be some sort of more detailed explanation for the disruption and an apology, but instead it was simply some "trumpet blowing" about the addition of the 1939 register. That's great, incidentally, but it seems significantly poorer than FMP's 1939 implementation, which has more accurate transcriptions and things like proper street addresses which, unlike in Ancestry, are shown in the transcription even if they're obscured by an "officially closed" in the image itself. It makes it more difficult to decide if I should continue with my FMP subscription, which I use mainly for the 1939, as well as Ancestry.