55 day interest free period t's & c's

motoko

I recently started spending on a balance transfer card, with the intention of paying the balance of my next statement in full (including the bt) to avoid any interest on the purchases. However I'm not sure whether I've screwed up, since I've now realised the 55 day interest free period is also affected by whether you also paid the previous statement in full (which I didn't). Usually I am able to decipher most t's & c's, but I'm not sure if I'm reading these correctly, so I thought I'd post them here to see what anyone else makes of them (the card in question is m&s):

"Interest is charged from the dates those items are charged to the Account. In all cases (other than, for Purchases only, where one of the below alternatives applies) interest will be charged on a daily basis until the outstanding balance on the Account has been repaid in full and will be added to the Account monthly on the statement date. The alternatives for Purchases are that:

• you (a) repay in full the “present balance” shown as outstanding on your current statement by close of business on the Repayment Date and (b) also did so in relation to the “present balance” shown as outstanding on the previous statement - in which case no interest will be charged in relation to that current statement on Purchases (excluding Cash Advances and Balance Transfers) which form part of the amounts shown on that current statement as being or having been outstanding at any point; or

• you (a) repay in full the “present balance” shown as outstanding on your current statement by close of business on the Repayment Date, but (b) did not do so in relation to the “present balance” shown as outstanding on the previous statement - in which case interest will be charged on a daily basis in relation to that current statement on Purchases (excluding Cash Advances and Balance Transfers) which form part of the amounts shown on that current statement as being or having been outstanding at any point from the date those Purchases were charged to the Account until the date of that current statement."

My understanding of this is:
Paragraph 1: Normally you pay interest on everything from the day its charged to the card until the day you pay it off.
Paragraph 2: If you paid both your previous & current statement balances in full, then you won't pay any interest on any purchases on the current statement. Which unfortunately doesn't apply to me.
Paragraph 3: If you paid your current statement but not your previous statement in full, you pay interest on purchases that were "outstanding" prior to the current statement. This definitely will apply to me, and I think it means you would pay interest on those purchases which were already on your previous statement, but not on those charged to the account since your previous statement.

If I've understood this right, then that's fine as there were no purchases on my previous statement, only my balance transfer which I fully expected to be paying interest (@ 3.9%) on anyway. However, I can't find anywhere what it means by "outstanding", I am assuming it means it has appeared on a previous statement, simply because I can't think of anything else it could mean. If anyone can shed any light on this, or let me know your opinion, it would be very helpful.