Also don't holds usually stay longer on credit cards vs debit cards
Card shouldn't make much difference.. It's really down to the payment processor, and sometimes the retailer if they fail to release the hold and just let it time out.. I've seen holds drop in a couple of minutes when done properly (eg. SodaStream, who use it as part of their web ordering service.. it puts a hold on as you fill your basket and releases if you leave the website without buying). I've seen it take 2 weeks.. I had one that kept renewing the hold even though no money was owing until I had the bank remove it (Ecotricity, you'll be unsurprised to learn).
Credit card companies may process it slower as typically you don't have live notification of your balance since it really only matters at the end of a month.
Was digging out the fuel transaction rules and I found some EV charging transaction rules I didn't know about...
"Each electric vehicle charging Transaction for which authorization is requested before vehicle charging begins is properly processed as follows:"
"If the Transaction is finalized for an amount that: a. Exceeds the authorized amount, then the Acquirer must send an additional (incremental) authorization request for the unauthorized amount (refer to section 2.9); or record. b. Is less than the authorized amount, then within 24 hours of finalization, the Acquirer must either send a partial reversal for the excess authorized amount, or submit the Transaction clearing 4. In the case of a Transaction cancelled by the Cardholder, then within 24 hours, the Acquirer must send a full reversal request."
So the rules aren't as strict as for fuel.. For reference the fuel section contains this:
"Within 60 minutes of receiving the advice message, the Issuer must release any hold that the Issuer placed on the Cardholder’s available funds or credit in excess of the Transaction amount specified in DE 4 (Amount, Transaction"
(This has changed since I last read it, they've relaxed it I think).