My
boat is in the same situation.
I have removed all the old bottom paint etc. and applying all new this spring.
The person doing it has been doing this for many years and probably the most respected fibreglass,
gelcoat, paint and everything else to do with the
hull of a fibreglass boat in eastern
Ontario &
New York state.
He told me that he will not do anything until the temperature has been at least +10 for a week.
That will ensure the hull is dry and up to temperature.
He said he prefers it to be above +15, but that depends on so many things, such as when I want to re-commission my boat and how many boats he has lined up.