I think you have the same 204h timing issue. Would not the increase in hours requirement result in an expected decrease in the rate of accrual? In which case your amendment could not take effect until after 1/1 and then participants would already have earned an accrual, at least on 2020 comp to date. Also be careful in case you have any flat dollar credits. If all participants were expected to work 1000+ hours then maybe the amendment would not necessitate a 204h notice - but remember that IRS can take a series of amendments and consider them as one, the reason being to prevent circumvention of various rules, which is what you are trying to do here, so a savvy agent (don't laugh people) could say you did not comply with 204h on that basis. I would tread lightly, do 204h now and freeze effective 15 days hence and provide minimal 2020 credit (assuming no flat dollar amounts, especially for HCEs). If the first 2020 payroll doesn't happen until 1/10 say, then maybe your argument can be zero plan compensation thru 1/3, for example, and so no credits on that basis. Good luck