They already are term time here. It changed a few years back. Those on much older contracts kept some of their terms and conditions, inc some pay, but newer staff didn't. At my school no one is on the old terms and pay anymore though.
I think it's term time plus 4 weeks holiday often.
And pro rats right down to exact hours. Often meetings etc have to be dealt with with management in school - our tas are expected to attend meetings after school but the time comes out of lunch time - so a one hour meeting means the ta gets two one hour lunch breaks a week instead of all 30 minute ones. Don't get paid for 15 min morning break either.