Instant

By default, speed255 only checks for new entities every 5 seconds, to reduce impact on performance.

This will mean that an entity won't have it's tag applied instantly, and instead could have a delay between the time the tag was given, and the time the tag took effect.

Giving an entity instant bypasses this delay, allowing the effects to take place immediately.

Instant is considered a temporary tag, and is removed automatically when it's effects have taken place.

Using the instant tag

To summon an entity with the instant tag:
/summon villager ~ ~ ~ {Tags:["instant","entity-data","silent"]}
(silent is an example of a tag that should apply instantly)

Tag	Command
instant	tag @t add s255--entity - tag @t remove instant