I would say it is prudent to not add any boost at this time.
Regardless of brand.
Ya, we are overdue for a variant, but maybe people aren’t reading about other countries, where the odds are it will appear.
So your perspective would be don’t boost until there’s significant danger. There might not be until 1) August when every vax is dead and a re-surge of a current variant may appear or 2) when there is news from somewhere about one. Then get it so two weeks can pass.