Baldwin bunq is not the issue here. Bunq supports the RT1 and TIPS systems, the two largest Instant Payment networks in Europe.
It's often the other bank not supporting RT1 and/or TIPS. There's nothing bunq can do about it. ING, for example, only supports receiving money using the TIPS network, but doesn't support sending money using the TIPS network.
If a transfer cannot be sent as an Instant Payment, because the sending and receiving bank don't support the same network, the payment is sent as a regular SEPA transfer. Those take 1-2 business days.
