How long did it take you to move up through the limits?

Just interested to know how long it took people to move up through the ranks of the nano / micro limits? (and how many hours / week were you playing on average?)

I plan on "doing my time" on the following limit games:
0.02/0.04
0.05/0.10
0.25/0.50
0.50/1.00
1.00/2.00
2.00/4.00

I will build up a 300BB BR before stepping to the next limit.

I can only afford to play approx 10 hrs per week- other commitment as well as poker I'm afraid. I do have a few other hours per week for studying / reading books, etc.

Any idea what time spans I am looking at?

Many thanks,
Ian