Actually it doesn't bump at all when doing at atm pressure,boiling stones are not needed.And don't use NaOH,it's weaker base and yields will be low or close to nothing,does the price of KOH really outweigh the cost of lost safrole due lower yields?You might also want to check out this:
Post 431957 (https://www.thevespiary.org/talk/index.php?topic=9698.msg43195700#msg43195700)
(raffike: "CaO/KOH isomerizing procedure is nicely scaleable", Methods Discourse)