Hi Robin & Bill,
I had a cheap-n-cheerful Qumox intervalometer which I used with 1000D for transit of Venus because I could programme in delays, exposure etc. I thought it had such a facility. If I remember rightly I could programme the timer with delay, exposure time, interval between shots and number of shots up to 999 I think. With 1000D set to ‘bulb’ and then switched to liveview the mirror came up then timer went through the sequence – delay – exposure – mirror dropped down and lifted again immediately- interval – exposure – mirror drop & lift etc. I’ll try to find it to check.