no, you have not to unlearn, and won't lose experience gained in an occupation. Only, when you give up an occupation, you cannot retake it before 46hrs elapsed. In fact, you may practise 4.5 occupations per day, because you may practise one, give it up afterwards, then take another one and practise it. The maximum of occupations doable during a day is 6 (giving up 3 after practising, taking 3 new ones), but due to the 2day cooldown it boils down to an average maximum of 4.5 - I did that in the old times in order to get as much products as possible for alchemy potions and cats crafting.
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Daomei die Streunerin - religionsneutral, zivilisationsneutral, gildenneutral