I feel that this would be reeeally, really useful. A term that wraps up this sentence nicely would be swell:
'Yes, though as of during now till then if I think of a logically sound reason why the thing I just agreed to is actually kinda dumb, I would like the option to not do/attend said thing at any time, without it looking irresponsible'.
Because if there's not a term to describe all that. Then there needs to be.