Hi Ms.K, we too are going to be on this cruise, well if they can find us a stateroom, we are still showing blank
The ship is very likely to arrive in Geiranger before 12:00, but may not have it's tender service running for a while after that as they have to (a) get clearance to come ashore, (b) set up the dockside security systems, (c) clear priority passengers ashore first.
On top of that we have to send tours off in Hellesylt, which could be a lengthy affair depending on the number of tenders lowered, used, then recovered.
Given the time that any of these 'unknowns' could add to you getting ashore, I would personally be very hesitant to book the 12:30 tour.
As it is a short run from the quayside to the ship, the last tender tends to be only 15 minutes or so before departure, so the later option would sound "safer" to me.
Have you asked the operator of the likelihood of being able to book the later trip, then jump on the earlier one if you are ashore in time? They may be willing to do that.
One last thought, if you were to miss the ship, there is a bus from Geiranger to our next port of call, so you could try & play catchup. But beware, I have known of ships failing to dock in Alesund, so it could be a big risk.
Here's to finding some good weather,