osram apparently doesn't sell by bins, but by batches, so you never know what you get
Yeah,
If you buy a reel of 2t-3t you either get all 2t or all 3t.
To (maybe) get 4t you have to buy 3t4t, and when you get them you'll know if they are 3t .. or 4t ..
I know that 2 years ago, Osram were still not producing enough of 4T relative to 3T for them to be reasonably frequent. It looks like things haven't changed very much ...
I bought my 3Ts 3 years ago, and they are still the most readily available top bin deep red ...
I believe we might see something similar with cree cobs now : less rolling out of new bins, but prices coming down gradually ... just me speculating tho.