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Depends on your needs and available time.
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TR is not necessarily setup for the ultra distance type of rides and races specifically. It is primarily aimed at time-crunched athletes, looking at events ranging around 1 hour up to 8-12 hours for the longer events (full distance triathlon, centuries, gravel etc.)
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With the time limits above, their common recommendations cap out around 3 hour rides (although there are many in the catalog that exceed that).
So, for those stepping into events well beyond those common bounds, you have to get a bit creative. I recommend reviewing some of the other ultra threads around here, for some great advice, directed more towards your needs.