Oldschool Runescape's top 5 player overall, He Box Jonge, achieved 200 million sailing XP while:
Renovating his home
Averaging 4 hours of sleep per night
Drank only water, no caffeine
Took 8 straight weeks to get
Being a 6'2 200 pound bodybuilder
I need to grind harder
@OsrsF2PBots I'm not sure, but is around 6 to 9 months, i didn't track how many time it was for me, probably like 8 months, also when is full you will know when you try to regain you %, it will tell you the storeroom is full and no more decrease occurs