essentially yes if the amount you set is 30 buy ins for that game... you cna have aggressive BRM or safe BRM... aggressive may be 20 buy ins safe may be 50 buy ins (specifically for SNG). SNG's are the 'safest' form of poker where you shouldn't lose it all fast but you won't win quickly either... it is a grind where you can make a slow but solid amount.. So answer to your question is if you set 30BI as the minimum amount then yes you should step down until you have £45 again.
I totally disagree with this answer. You need to play within your
skill level and bankroll. There is going to be swings, but in SNGs it shouldn't be that bad. If you can beat a 1.50 SNG you shouldn't have a problem with 30 buy-ins.
You catch a bad beat or two, go card dead on one, ect... these things happen. But if you can beat 1.50, you should have 3 or 4 cashes in a row also. I don't understand how it helps to drop down
and win less when the cards are running good for you. You should be confident and stick to the level you should be at. If you lose your whole bankroll
what that really means is you are not on par with the other players, not that you mismanaged the bankroll.
To follow this logic, when you lose you drop down,
when you win you should move up....which is not true in a small sample of games.