Thanks everyone, I'll look at the padlock tags. I think I had read about them here some while ago and it prompted me to ask about temp lamb tags.
We are due 40-50 lambs, about half of which should be female and I could try temp tags on them. While I can respray at vaccination time...we don't shear (self shedding Wilts) and I naturally wean the lambs, they are only separated from ewes a few weeks before tupping. So we don't generally round up the lambs as often as some and I therefore have less opportunity to respray.
Does anyone know if I could just write a number with a Sharpie pen (for my own reference) on the generic EID slaughter tags, which I have lying around anyway for boy lambs...or would a Sharpie marked tags be rejected at the abattoir? The ewe lambs I decided to keep could have this EID tag cut out in around September time and then retagged with appropriate double tag (reusing the hole from the generic EID tag)...if that all makes sense?