I just hobbled this together so it’s subject to corrections 
| Program Type | Calendar | Periodized | Phased | Ramp Rate | Adjust Periodization Level | Adjust Polarization Level | Adjust Recovery Demands | Adjust XSS/hour* | Adjust Freshness Feedback |
|---|---|---|---|---|---|---|---|---|---|
| XATA Continuous | Blank | DIY | DIY | DIY | No; DIY | Yes | Yes | DIY | Yes |
| XATA Base-Build-Peak | Blank | Yes | Yes | DIY | No; based on setup | Yes | Yes | DIY | Yes |
| XFAI Goal/Event/Race | Forecast: LIT/HIT/Rest | Yes | Yes | Variable (programmatic) | Yes | Yes | Yes | Yes | No; DIY |
*Raises or lowers high/peak strain on HIT days; i.e. more efficient with higher difficulty level or less efficient with lower difficulty. RD slider is most effective with shorter Focus Duration targets.
All program options support daily selection of workout activities, or you can ignore the day’s advice on occassion and do something else. Xert will adapt to whatever you decide to do. For example, skip a day, ride more/less than target, impromptu group ride, schedule conflict, etc.
All program types can be re-configured at any time. XFAI plans can be updated (recast) with new settings.
Both program types can be configured to automatically schedule a WOTD (workout of the day) on the Planner. As @manofsteele mentions this option randomly selects from top list of suitable entries based on the day’s target. You can over-ride that selection if you prefer by selecting an alternate at the last minute.
Both program types rely on calculated form to determine whether LIT, HIT or Rest is recommended.
XATA is more flexible especially if your schedule isn’t restricted. You’re in charge of managing ramp rate and Focus Duration.
XFAI is much more nuanced with a mapped out course to follow with a variable ramp rate applied during the periodized forecast.
Both types are subject to change based on your execution and any hiccups encountered along the way.
Both programs operate with progressive overload as long as your setup supports it. Confirm the deltas in Table Views for both signature and TL. An increase in TL over time is ideal. While you can continue to improve when your max hours top out, more time to train provides greater potential gain.
XATA Continuous is especially DIY-centric. You decide where to go, when to alter ramp rate, end a block of training, change Focus Duration, insert a recovery week, follow a preferred protocol (ex. polarized vs sweet spot), etc.
If you set an Improvement Rate and don’t manage it over time TL will continuously ramp up. The idea isn’t to follow the advice blindly but work with it. You want to exercise restraint and follow your gut if adequate recovery isn’t happening. If it feels like you’re digging a hole, you are. 
Back off as needed (lower ramp rate, make prudent selections or temporarily adjust Freshness Feedback) and resume to “normal” when ready. If consistently feeling stretched adjust Recovery Demands or take a recovery week. Be prepared to advise the advisor. You know yourself better than any algorithm does.
XATA Base-Build-Peak adds phased periodized logic running in background. But remember you’re still in control. 