Updated from 9:57 a.m. EST

Immediately after reporting earnings Tuesday evening that were well above expectations, shares of solar panel maker and utility scale project developer First Solar (FSLR) - Get Report were doing well. 

But despite a beat of 24 cents a share -- the company reported EPS of $1.24 on revenue of $480 million -- First Solar was tumbling more than 8% on Wednesday. 

Perhaps a downgrade to underperform from Credit Suisse's Andrew Hughes and Maheep Mandloi may have something to do with these volatile shares?

Guidance on project timing poses risks to the company's 2017 earnings estimates and could further impair the value of its yieldco 8Point3 Energy Partners (CAFD) , according to Credit Suisse. 

Furthermore, First Solar's book of business for 2018 seems unlikely to support three times earnings growth, and a valuation on normalized earnings trajectory isn't compelling following the stock's recent strong run, Hughes and Mandloi wrote Wednesday in a research report.

Indeed, First Solar's stock has risen 23% in the past three months despite tax concerns that have rippled through the industry since the Nov. 8 election of Donald Trump. 

Shares of industry peer Canadian Solar (CSIQ) - Get Report were also plummeting on Wednesday, down 8%, as the company was downgraded by JPMorgan. 

The firm said Canadian Solar's recovery will likely not be V-shaped, meaning the 25% appreciation this stock has experienced since Jan. 1 isn't here to stay. 

"We are hesitant to add to positions in this stock at this price level at this time, given what we believe will be a challenging 2017-2018 owing to industrywide manufacturing overcapacity, and lower y/y demand in key end markets," JPMorgan's Paul Coster wrote Wednesday. "Though module [average selling prices] have stabilized recently, we expect prices to slump again in [the second half of 2017], post the FIT reduction in China."

Such a negative note could sour the entire industry for investors Wednesday, and indeed much of the remaining solar panel manufacturers were trading down before the bell, including SunPower (SPWR) - Get Report, which last week soared after it reported slightly better-than-expected earnings. Some company followers asserted, however, that SunPower's rise likely had more to do with the immense short holding in the stock than the bottom line surprise. 

Even the U.S.-listed shares of some Chinese solar manufacturers were trending down Wednesday, including those of JinkoSolar (JKS) - Get Report and JA Solar (JASO) , though not as etensively. Many Chinese panel manufacturers have performed better than their U.S. counterparts during the current solar down-cycle largely due to lower in-house production costs. 

As Coster noted, however, Chinese feed-in tariff, or FIT, reductions are expected in the second half of the year. China's FIT program is similar to that of the U.S. Solar Tax Credit program, in that it provides economical incentives for solar panel project operators to have projects tapped into the grid. 

Industry followers have speculated a solar panel demand pull-in ahead of this FIT cut, as project operators rush to complete projects and tap into the grid ahead of the cutoff, after which this demand should fall off.