Expanded Octet and Resonance

[Manya Kidambi 3I]

Can an atom without an expanded octet have resonance with more than 4 single bonds?

[904914909]

No, because having more than 4 single bonds would consist of an expanded octet. To have more than 4 single bonds the atom would have to be in the 3p block or higher.

[Mariam Baghdasaryan 4F]

I don't think it can because if it has more than 4 single bonds, then that means the central atom has more than 8 valence electrons, already suggesting an expanded octet. The resonance structures also have to reflect this. If an atom does not have a d-orbital or f-orbital for more electrons, it can't have more than 4 bonds.