to big d1
senario: You have 2 dest. alternate. Over destination you have 2 options when decide to divert. First options go to 1. alternate 2. options go to 2. alternate. 1. alternate requires 1000 kg. 2. alternate requires 2500 kg. At planning stage you have to put 2500 as alternate fuel.
eu-ops appendix 1 to ops 1.255 Fuel Policy says :
(b) where two destination alternate aerodromes are required in accordance with OPS 1.295(d), be sufficient to proceed to the alternate aerodrome which requires the greater amount of alternate fuel.
Your saying is different. You said (Your comment about "do you have to have enough fuel to divert to alt 2 if you do divert to alt 1). This is completely different.