In reply to subtle:
I was up Strathfarrar today (miserable weather, did a couple of the smaller marilyns rather than munros or corbetts seeing as it was all in the clag; bad day to realise when heading for the first summit that my rarely used GPS watch wasn't actually charged ... but ended up as good navigation practice, it's been a while since I had to use a map and compass so much)
....anyway, that asides, turns out there are some changes. The first gate has the normal access arrangements as per the website link above (i.e. 9am to 6pm in April), but I go go there once or twice a year and this is the first time there has been a second gate further down the glen requiring opening. The women who let me through the gates were both very helpful and nice to chat to, but said that there had been problems with the usual arrangements and so now the second gate at the signed entrance to the actual estate was having to be used. They said hillwalkers hadn't caused the problems and were still being allowed access as agreed, but it sounds like daytrippers/holidaymakers were maybe trying to get in late on in the day and either having no chance of getting back to the first gate by the closing time, or deliberately staying down the far end of the glen to try and stay overnight.
So for hill walkers (who will generally be arriving in the morning), things haven't really changed much asides from an extra gate to be opened. People arriving later in the day but still within the daily vehicle limit are only allowed through the first gate, not the next one several miles on.