I'm a bit confused at what you're referring to in terms of rescheduling and/or relief. The upcoming payments are maturing bonds the ECB holds, short-term treasury bills and loans owed to the IMF. The WSJ link earlier provides an interactive. The IMF isn't, as far as I'm aware, going to reschedule what's owed to them.
(Capital gains and interest on bonds the ECB holds are technically returned, at the discretion of the ECB and on the basis that Greece remains in a programme. There's a tranche of these currently in limbo though, as pointed out earlier in the thread.)
If I understand the response to an earlier post in the thread correctly, if they're able to retire the IMF programme, with European institutional/bilateral funding, then they'd be able to push this down the road and provide breathing space.