Plan Change While Beta ?

No. You will not keep beta pricing if you change the plan. Beta pricing will end soon. Introductory pricing will end soon as well.

If you change your plan now, you will end up with existing Introductory/Launch price. However u can try to buy an add-on that meets your need.

For Beta Testers, Fizz emailed Nov 21 . . . " You will be notified well before your three-month discount comes to an end. And at that point in time, you will still have access to the introductory prices we revealed today.

All good things must come to an end.
The mobile introductory prices will end next April. Why not make the most of it by inviting a friend to join Fizz, you will both earn a $25 referral bonus.

Toute bonne chose a une fin.
Les prix de lancement prendront fin en avril prochain. Profitez-en pour inviter vos amis à se joindre à la communauté Fizz, vous obtiendrez chacun une prime de référence de 25 $.

(Source: https://www.facebook.com/fizzca/)