Processing times for F2B vs F4

[Rail-worker]

Hello everyone,

Currently, I (US citizen) am thinking of requesting an immigrant visa for my father who lives in a European country. They are telling me the average overall processing time for this is about 9 months. I also want to bring my sisters (unmarried, 21 yo and older) from the same country.

Would it be better for me as a sibling to fill an I-130 asking for an F4 visa (siblings of US citizens) or it would be better to wait for my father to come and once he is here as a permanent resident (a few weeks after he arrives) to fill for the F2B ( unmarried sons and daughters of permanent residents)?

If you could only pick one way what would you pick?
I really appreciate any help you can provide.

[newacct]

You can look at the Visa bulletin https://www.immihelp.com/visa-bulletin/ yourself. As you can see, F2B has a much shorter wait for visa numbers than F4 for every country of birth except Mexico (where it is only slightly shorter). But F2B requires that your sister remain unmarried until she immigrates. There is no problem with a person being the beneficiary of multiple petitions, so if you don't mind the cost, you could also petition her in addition to your father petitioning her, to serve as a backup in case your sister marries or your father dies or abandons residency during the wait.