Basically, all new plans have very high limits for both disk and bandwidth - beyond what was offered for either the Crazy Domain Insane plan or the Code Monster plan. You should also note that these old plans themselves were much better than the previous plans offered by DH in times long ago. Basically, as the years go by, the plans mostly get better and better. You'll note that none of the plans offer the callbacks that the code monster plan offered. The 3 callbacks that you got with the old Code Monster plan are available as an ala carte feature for $9.95 a month.
Old plans always continue to exist and continue to be available to renewing customers - that is, if you don't do anything, you renew into your old plan. This is a good deal for some customers - for instance, if you did 2-year prepayment on the old Crazy Domain Insane plan, you paid only $7.95 a month. You'd have to do a 3-year prepayment to access that rate under the new plan.
Regarding your exact situation, DH doubled the bandwidth for everyone under the old plans and at some point in the future will be doubling our disk limits. This should give you 800 GB of disk space and 8 TB of monthly transfer. To get an equivalent plan, you'd also need to sign up for the new $9.95 premium callback feature which was included in your old Code Monster plan. If you sign up for a 1 year prepayment on the new Happy Hosting plan with the callback feature, you'd pay ($9.95 + $9.95) * 12 = $238.80. Actually, I'm not sure if the 9% discount applies to the premium callback support, if it does, you'd pay $228.22 for a new annual plan. Parenthetically, if you were on a 2-year prepayment plan like I am, you'd actually pay more by switching to the new plan.
Anyway, my point is that even if you tried to replicate your old plan, it would be between $0.60-$11.18 cheaper but you would have slightly less disk and bandwidth.
Speaking of which, how much is your disk and bandwidth going up every week? Is it still 2GB disk a week and 32GB bandwidth a week or has it been increased?
I think every customer is in a different situation wrt how much better or worse the new plans are. There are clearly some customers who would benefit from switching - I'm speaking of the customers who were on the Code Monster plan for the extra disk and bandwidth and who didn't care about the callbacks. What's ironic is that the callbacks were the most valuable part of the plan even though I think most people picked that plan for the higher limits!
At any rate, you've picked up on the changes now and as Atropos has said, you can switch to the new plans with full credit for the unused portion of your renewed old plan. As per the analysis above, you do have a great deal to gain if you don't need the support callbacks. If you do want the callbacks, your decision probably hinges on how valuable you find the extra disk and bandwidth on your old plan.
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