Hilton HHonors - Visa promo book 4 nights, 4th is free. Latin America. + free upgrade

I got a weekly Hilton newsletter, and noticed that they're having a Visa promotion, book 4 nights, only pay for 3. One location in Ecuador I already have booked for September, so thought, I'd try and use this special. No luck.

Not for any days I check for in May, July, August or September (I just plug in some random dates). The only dates I find are ones for the next month or so. And they usually have another promotion that doesn't require all 4 nights, but work out to a decent discount as well. IE, 20% off flexible rates.

95% of the time when I get one of these promotional emails from Hilton, I get the same results. This promotion is from Jan 1-Dec 31st, and you'd think that might some real availability further along in the year.

Could you please post the URL to this promotion? Also, do you have a question you need answered or...??? Thanks

EDIT: I think this is what you are talking about:
http://www.hilton.com/en/hi/promotions/hi_visaamericasoffer/index.jhtml?adId=emailhilt,intl&cid=EM,HH,WeeklySpecials,Intl

Could you please post the URL to this promotion? Also, do you have a question you need answered or...??? Thanks

EDIT: I think this is what you are talking about:
http://www.hilton.com/en/hi/promotions/hi_visaamericasoffer/index.jhtml?adId=emailhilt,intl&cid=EM,HH,WeeklySpecials,Intl

Yes, that's the promotion.

The question would be, why do they release these promotions that are often unusable? I found some dates in February, and that's it. The promotion runs until the end of the year. I understand that there may be high season times when the special isn't available, but checking random blocks of 4 nights from May-Sept have yielded no program nights.

A few months back, they had all these cheap promos in Europe around Thanksgiving. Nothing ever available.

I think the only one of the promotions that I ever got to work was pay for 2, get 1 free in Melbourne last year, and even then, the website wasn't even accurate. They said the deal was over, while the hotel confirmed that it was still valid for their hotel.

I tried to book this for separate 3 dates for the nice Caribe Hilton in Puerto Rico but each time it said "rate not available". The hotel is quite busy so I can understand. I have used similar promos in the past but during less busy times.

MisterNice

I did find quite a few dates available in the hotels I checked but in most cases the savings were minimal over the 20% discount that the OP mentioned. Usually only $40 or so over a fourth-night-free rate when I was looking at just the basic room. A little better savings if you were looking at suites but still not very impressive.