В случае расхождении сведений,

[Pal'mira]

Датой осуществленной заправки ВС топливом является дата, указанная в заправочном требовании и (или) инвойсе. В случае расхождении сведений, содержащихся в заправочном требовании и инвойсе, преимущество имеет заправочное требование.

Should there be any difference between delivery ticket and invoice, delivery ticket shall prevail.
вроде как-то так....

[Elenka_M]

IMHO, лучше не difference, a discrepancy

[Mary_G]

If data in delivery ticket and invoice differ, then ....
Should delivery ticket be different from invoice, then...

[foxtrot]

Option:
The a/c [grade] fuel shipment date shall be the date indicated/specified in a relevant fuel request or invoice. Should dates indicated in a fuel request and invoice differ the fuel request shall prevail

[Pal'mira]

спасибо!
написала: The aircraft refuelling date shall be the date specified in a relevant fuel request or invoice. Should dates indicated in a fuel request and invoice differ the fuel request shall prevail

[Translucid Mushroom]

also consider в случае расхождениЯ сведений