I think that is reasonable. You want your Holter, when it comes at about the 10-12 week mark, to show a veridical assessment of your heart's robustness-in-rhythm. If you are on meds that might alter that picture, I would hope you have instructions to alter the prescription, including stopping them altogether, at least a couple of days before the Holter. For example, what is the point of taking metoprolol or propafenone while trying to find out if the ablation worked?!?!? No, you want to have been off those, or any others except maybe a statin and a DOAC (Direct Oral Anti-Coagulant like rivaroxaban or apixaban, Xarelto or Eliquis) so that the heart's true performance, unaided, can be shown to the person analyzing the results and thence to you.