Unique Local Address (ULA) - IPv6

Hi all

Would like some clarification on configuring ulas.
We all know its: FC00::/7, however as per RFC4193 it mentions that the L bit
(the 8th bit) is set to 1 if the prefix is locally assigned, and that L bit
as 0 is undefined.
As such in various places, Ive seen that you'd typically configure ulas
starting as fd00::/8, but from a Cisco implementation perspective,
does it matter whether fc00::/8 or fd00::/8 is used?

From a lab perspective, if asked to configure a ula, should ipv6 address
fd00:... always be used (locally assigning the ipv6 address) ?

Please advise.

-- 
Regards
Roy
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