Jamieson, Fausset and Brown on Philippians 4:10

10. But--transitional conjunction. But "now" to pass to another subject.

in the Lord--He views everything with reference to Christ.

at the last--"at last"; implying he was expecting their gift, not from a selfish view, but as a "fruit" of their faith, and to "abound" to their account (Php 4:11, 17). Though long in coming, owing to Epaphroditus' sickness and other delays, he does not imply their gift was too late.

your care ... hath flourished again--Greek, "Ye have flourished again (revived, as trees sprouting forth again in spring) in your care for me."

wherein ye were also careful--in respect to which (revival, namely, the sending of a supply to me) "ye were also (all along) careful, but ye lacked opportunity"; whether from want of means or want of a messenger. Your "lack of service" (Php 2:30), was owing to your having "lacked opportunity."