I suspect you'll have to pay half of the full price ($29.95 / 2 = $14,98), since this is a major upgrade
We always provide free upgrades for our software through sub-point upgrades. This means that version 5.6 will be a free upgrade from 5.0 all the way to a hypothetical 5.99. Major version upgrades such as 5.x to 6.x incur a price of 50% of the retail price. We also provide free upgrades from one major point release to the next if you have purchased within the last 3 months of release.
If you currently own Pocket Informant 5.xx and want to upgrade to a newer version of 5.xx - just simply download the latest installer and install over your current installation. Its that simple with no validation necessary. Applicable to non-OEM releases only.