So I was just looking through some class ideas when I came across the Primeval Guardian Ranger archetype. Guardian Soul states that you assume a guardian form until you end it or are incapacitated. While under the effects, you become large, have 5 feet of movement, your reach increases by 5 feet, and the subject of question, you gain temporary hit points at the start of each of your turns equal to half of your ranger level. Typically, the temporary hit points are minimal, but do provide some padding. My question includes the pre-combat uses of the temporary hit points.
Temporary hit points last until they're either depleted, or you finish a long rest, or in the case of guardian soul, you leave the form. The form has no defined limit for how long it lasts, and instead lasts until you cancel it or are incapacitated. So at level 4, while in form you will gain 2 temporary hit points every round (every 6 seconds). on a larger scale, you will gain 20 per minute in form, 200 per 10 minutes, 1200 per hour, and a typical work day of 8 hours nets you 9600 temporary hit points while you retain Guardian Soul at level 4.
Is there a limit to how long you can retain Guardian Soul, and is there a limit to how much temporary health you can have?