Master Instructor:
You could do all that OR...someone could take just as much time and just answer your question(s).
1. You will NOT be at sea your first 4 years, you will be posted to a ship - That ship will have sea time. The averages for any given 12-month period are:
High Readiness: 4 - 6 months;
Normal Readiness: 2 - 4 months; and
Reduced Readiness: Measured in weeks.
Keep in mind that due to manning shortages, you MAY be bounced from ship to ship but guaranteed, you will have some ‘me’ time – we actually have CANFORGENs/MARGENs etc (rules) to ensure this.
Now someone will chime in and say “I was on HMCS XXXXX and we were gone for 8 months one year.” This happens VERY rarely and I believe the last time was CHARLOTTETOWN and possibly VANCOUVER in 2001-2002.
2. Kratz is correct - There is no such thing as Corporal in the Navy – some Captains actually used to insist that Corporals/Sergeants etc. in the support trades (Cooks, Clerks, Supply…) be called LS/PO2 etc once on a ship. To answer your question however, if you keep your nose clean (behave yourself in and out of uniform; at work and away from work), you will get your LS rank in 48 months, 36 if you are really keen and your supervisor(s) put you up for advance promotion. Hint here – This will be the ONLY promotion you will likely get ‘on time’.
Hope this helps!! And best of Luck!