Instilling an effect over non-consecutive seasons

Call me dumb, but I've never realized that someone instilling an effect into a enchanted device (greater or talisman) might do so in non-consecutive seasons.

So the magus could instill power in one season, spend some time studying or working on another project, then come back and instill some more. Essentially, investing an effect over years just because he's not concentrating on that project over others.

Am I correct?

Yup.

Absolutely!

Further, it doesn't have to be the same magus installing the various powers in a single greater device (NOT Talisman!).

The real question is: if an enchantment is going to take me more than one season (my Lab Total is 50 and the effect is level 35, or something) - can those seasons even be nonconsecutive?

That's just another way of stating the OP, and we are saying that's fine.

I can find nothing in the core book to suggest this cannot be done.
See above answers for result.