[mythtv-users] Responsiveness of zap2it to lineup discrepancies?

[f-myth-users at media.mit.edu]

I now have a different problem.  (Should I have started a new thread?)

Okay, I was all set to rearrange my channels according to mtdean's
advice---and then I discovered that, without warning, zap2it had
actually fixed their lineups.  It may have had something to do with
the message I sent them with an all-uppercase subject line over the
holiday weekend complaining that it had been 7 months since I'd
reported the discrepancy (along with forwarded copies of the mail).
Or maybe they changed it behind my back at some other point and I
somehow failed to notice, because---

---Myth is still reporting the contents of what -used- to be listed as
channels 84 & 85 (but have actually been on 71 & 72 for months) as
being on 84 & 85, and 71 & 72 aren't listed.  I tried getting listing
data from Myth for the last day in its current database, in case a
recent fetch might have fixed it at least there, but no such luck---
either the fetch hasn't happened recently enough, or this needs manual
resetting.

So:  I'm not sure if this will gradually fix itself over the next 2
weeks or not (I think I'd have to wait a day or two to even have any
idea), and I'm unwilling to wait 2 weeks to get accurate data for
these channels since there are things I'd like to record -right now-
which is why it's become an issue again.  I'm still running 0.18.1
without SVN's fancy --do-channel-updates arg to mythfilldatabase, so
what's the best way to accomplish this?  Should I go into mythtv-setup
and tell it to clear all my channel settings, and then re-add all my
video sources?  (Seems risky, but maybe it's not if it won't wind up
bashing all my recording rules; will this work if I -don't- also clear
all my cards?  I -really- don't want to do that.)  Should I clear some
mysql table instead?  (I assume either way I need to then rerun
mythfilldatabase---are there any particular args I need to specify?)

I don't have any qualms about asking for all 13 days of listings
data if it's a one-shot (just me, just once, to recover from 7 months
of their incorrect listings), but I'm unsure if that's the way to even
fix this in the first place or how exactly to pull that off safely.
(And since I installed this from a package, I'd rather not risk
recompiling mythfilldatabase by hand to enable its defaultly-disabled
switch to grab all the listings data because I don't necessarily know
if my build environment would be consistent---geez, I wish this hadn't
been deliberately hidden in this way.)

Thanks!