As with all things, a degree of flexibility helps. My own career as a player may occasionally mean I have to move lessons, and so I'm fully understanding when you need to move them too. Clear communication and plenty of notice can usually sort things out to everyones satisfaction. However...the starting point needs to be the intention of a regular time slot.
Punctuality is essential, not because I love it (in all honesty I don't really) but because your lesson needs to end on time (often someone else will have a lesson after you) if we start late you'll end up with a frustratingly short lesson.
First lesson on a one off cash or online payment basis
All subsequent adult lessons are to be pre-paid in groups of four
Children and teenagers book a full 36 week year (less if not starting at the beginning of the academic year) in three 12 week terms, paid by standing order; 6 weeks notice are required for cancellations
At least 24hrs notice is required for individual cancellations or rescheduling of lessons or full fee is chargeable - pre payments wil just roll over to a later lesson. I'll always endeavour to find a replacement slot or you can find and book another slot that week online yourself.
Evenings slots are dedicated, once you have a space that is yours and so regular attendance is required
Day time adult lessons are on an ad hoc hoc basis, it's handy to have a regular slot, but not obligatory to keep to it.
Adult evening lessons – if multiple lessons are missed or cancelled then it will be reviewed mutually to find a better time slot, or shift to dropping in to open slots when available