Hello Roy, my pleasure!
I have tried to collect some information about B-463 and B-456 types here:
http://www.shipspotting.com/gallery/photo.php?lid=2774143
Thank you for bringing up more vessels. As I understand, you mean this one:

917 ZEELANDIA, IMO 7811484, van der Giessen-de Noord BV - Krimpen a/d Ijssel, 1980;
http://www.shipspotting.com/ships/ship.php?imo=7811484

and also this pair from CGM, apparently designed as gearless:

Y26 FORT SAINT CHARLES, IMO 7809869, Chantiers de l'Atlantique - St. Nazaire, 1980;
http://www.shipspotting.com/ships/ship.php?imo=7809869

Z26 FORT DESAIX, IMO 7809871, Chantiers de l'Atlantique - St. Nazaire, 1980;
http://www.shipspotting.com/ships/ship.php?imo=7809871

Looking for yard number of "Fort Saint Charles" I have found a site with many articles and details collected. Enjoy :)
http://www.maquettes-marmar.net/fichemaq/fdesaix/fdesaix.html

Thanks for the thorough info Marcin.

Indeed based on B463 of which nine were built.
Other ships based on B463 was La Fayette (B456) built for CGM. She was more or less the same as B463 though she had a bigger reefer capacity (CONAIR type) and more auxiliary engines.

Then there was the Zeelandia built by Van der Giessen-de Noord in the Netherlands. She was based on the Holandia (B463-II) though with quite some differences.

Then there were the Fort Desaix and Fort Saint Charles built by Chantiers de L' Atlantique, France.
They were loosely based on B463.

Cheers,
Roy

First new full container ships were ordered by Polish Ocean Lines in Gdańsk Shipyard, in January 1982, for Far East route.
Different economical difficulties and other factors caused, that the delivery was postponed to years 1988-1991.
The base for the design was B-463 container ship series, built by Gdańsk Shipyard for export:
http://www.shipspotting.com/photos/2774143
The B-355 series had identical particulars, 1513 (later: 1635) TEU capacity, only passive rolling damping and no cargo gear.
First (and perhaps also second) vessel had Sulzer-Cegielski 6RLB90 engine, rated for 21600 hp and some 19,2 kn speed,
(max. 24000 hp and up to 21,0 kn). Next vessels had Sulzer-Cegielski 6RTA76 with 22100hp. All had five-bladed propellers.

B355/1 H. CEGIELSKI, IMO 8302143, 1988, Polish Ocean Lines;
http://www.shipspotting.com/ships/ship.php?imo=8302143

B355/2 T. WENDA, IMO 8302155, 1989, Polish Ocean Lines;
http://www.shipspotting.com/ships/ship.php?imo=8302155

First two ships joined East-Asia Container Service (EACON SERVICE) created by PLO with East German DSR.
As Germany got united, the ships were moved to Joint Overseas Service (JOS) created by PLO with CMA.
In year 1991 the ships were sold to Egon Oldendorff. Third vessel joined JOS directly after commissioning:

B355/3 A. ABRAHAM, IMO 8302167, 1991, Polish Ocean Lines (Cyprus flag);
http://www.shipspotting.com/ships/ship.php?imo=8302167

But she was sold to Nordeutsche Reederei already in 1992, together with fourth vessel, still under construction for PLO:

B355/4 NORTHERN JOY, IMO 9039250, 1992; (planned PLO name: Z. KIETURAKIS) - still in service in 2020;
http://www.shipspotting.com/ships/ship.php?imo=9039250