How long before an Aldon sealer needs to be reapplied?

Aldon sealers don't break down - indoors or outside. Therefore, the question relates to dulling or wear of a glossy finish. A touch up of a dulled finish is just a light application for looks and is much quicker and easier than a full seal job. Depending on traffic volume, grit, etc. - touch up might not be needed for a couple of years or longer.

Note:

A glossy finish will not need touch up if a coating of Lifeguard is maintained on top. The Lifeguard protects the sealer and therefore, the sealer would not even need occasional touch up.

Note:
Sometimes, despite your diligent research and the best of intentions of your suppliers salesperson, you might have been given the wrong information. Therefore, no matter how confident you are, whether first time user or seasoned professional, it just makes good sense to patch test a small area and evaluate the results in a few hours before doing a large area.

Most Aldon sealers have more than one area they can be used in any project. Check sealer information on the web site.