According to the spell description of the Flock of Familiars spell:
If you already have a familiar conjured by the find familiar spell or similar means, then one fewer familiars are conjured by this spell.
Which would be fine if the Familiars conjured by the Find Familiar spell are equivalent to the familiars conjured by the Flock of Familiars spell, but in their respective spell descriptions the ranges for telepathic communication are 100 feet for a Find Familiar and 1 mile for a Flock of Familiars.
The description of Find Familiar says:
While your familiar is within 100 feet of you, you can communicate with it telepathically.
The description of Flock of Familiars says:
Familiars summoned by this spell can telepathically communicate with you and share their visual or auditory senses while they are within 1 mile of you.
RAW, does the range of your telepathic communication with your original familiar from Find Familiar increase to 1 mile when you cast Flock of Familiars?
Or does this mean that already having conjured a familiar through Find Familiar and then casting Flock of Familiars causes you to be worse off - during the one hour Flock of Familiars lasts - than if you had only casted Flock of Familiars?
1 From p. 57 of the digitally published adventure, Lost Laboratory of Kwalish